Heater unit



W. STEPHAN Sept. 12, 1950 H ATER UNIT Sheets-Sheet 1 Filed Oct. v15, 1946 J8 'INVENTOQ WOLFGANG S T E PHAN B)- %//W ATTORNEY W. STEPHAN I HEATER UNIT Sept. 12, 1950 2 Sheets-Sheet 2 Filed Oct. 15,1946

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Patented Sept. 12, 1950 HEATER UNIT Wolfgang Stephan, Demarest, N. J., assignor to S. Blickman, Ina, Weehawken, N. J a corporation of New York 7 Application October 1-5, 1946, Serial No. 703,311

3 Claims.

This invention relates to an improved heater unit, and its object is to provide a removable self contained electric heater and its control devices, of simple, inexpensive and compact construction and attractive appearance.

Other objects are to eliminate loose electric conductors, to make all of the parts of the unit readily accessible and to provide units which are interchangeable and easily replaced.

These and otherobjects of the invention will appear in the following specification, and its novel features pointed out in claims.

Referring to the drawings,

Fig. 1 is a bottom plan View of an electric heater unit which is made according to and embodies. my invention, together with parts of a heating table shown in section;

Fig. 2 is a sectional front elevation of the unit shown in Fig. l and of a guide therefor. The section in this figure is taken on the line 2-4 of Fig. 1;

Fig. 3 is a perspective View of a heating table equipped with a plurality of my novel heater units;

Fig. 4 is a perspective view of a part of theheating table, with one of the units partly withdrawn from it;

Fig. 5 is a sectional side elevation of a part of a heating table and a part of one of the units disclosed herein. The section in this figure is taken on the broken line 5-5 of Fig. 1.

The unit, of which a, preferred construction is illustrated, comprises a thin elongated rectangular slab Ill, the longitudinal edges of which are undercut, as shown at H, I2. Within the slab resistance elements 13, It are embedded. These elements are indicated diagrammatically in Fig. 1. The terminals of the coils l3 are designated by the reference numerals l5, l6, and the terminals of the coils M are designated by the reference numerals ll, [8.

An angle bracket 20 at the rear end of the slab supports a pair of contacts 25, 22, which are disposed in parallelism with the longitudinal. edges of the slab. In the arrangement shown, the contact 2| is connected by a conductor 23 to the terminal l5, and the contact 22 is connected by a conductor 24 to the terminal 18. 25 is an angle bracket at the front end of the slab adjustably connected to the slab by means of screws 26, which pass through slots 21 in one of the flanges of the angle bracket into the slab. A face plate 28 is afiixed to the other flange Of the angle bracket.

30 is an adjustable thermostat, which of itself 2. forms no part of my invention. As sh0wn,'it comprises a cam 3H affixed to a shaft 32, which passes through the face plateQt and hasa handle 33 on its outer end. The thermostat has a pair of terminals designatedby the reference numerals 34, 35. The terminal 34 is shown connected to the terminal terminal 35 isconriccted. to. the terminal ll by a conductor 31.

It is to be noted that all of the parts thus described are attached directly to the under side.

of the slab I'll, leaving its upper surface unencumbered, and thus its efficiency is enhanced.

40 designates a heating table, having a front plate ll, a. back plate t2, and a top plate 43. Several spaced orifices are formed in the top plate for holding flanged receptacles M. Plates.

are Welded to the bottoms of these receptacles. The edges of these plates are bent downwardly and inwardly to form guides it for the slabs ill (see Fig. 2). Spaced orifices -il are formed in the front plate ll for the reception of the units. Spring contacts 28, it are affixed to the back plate 42 in alinement with the contacts 2!, 22 when the slab it is supported on the guides 45. These contacts are to be connected to conductors from an electrical supply.

When the unit is inserted in a heating table through one of the orifices ll in the front plate, it is pushed in on the guides it until its contacts 2i, 22 engage the spring contacts 48, 49. Its face plate 28 will then abut the outer surface of the front plate M, as shown in Figs. 1 and 5, and may then be secured thereto by screws 38. The desired distance between the face plate and the contacts is obtained by adjusting the position of the angle bracket 25 on the slab ill.

Heat insulation, indicated by broken lines, is shown at I in Fig. 1 inside of the front and back plates 4 I A2 of the heating table, and also parallel with, but spaced from the longitudinal edges of the slab [0. The latter, when used, divides the heating table into compartments.

As shown in the drawings, the resistance elements I3, I 4, and th thermostat 30 are connected in series across the supply line, and a circuit can be established through them by turning the handle 33. This circuit will be broken automatically when a desired degree of temperature, determined by the setting of the thermostat, has been attained. The specific connections shown can be changed to connect the elements 13, M in parallel across the line and through the thermostat when it is desired to use the unit with a lower voltage.

It by a conductor 36, and the Various modifications in construction, mode of operation, method and use of an invention may, and do, occur to others, especially after benefitting from knowledge of such disclosures as that herein presented of the principles involved, but the invention itself is not confined to the present showing.

I claim:

1. A heating table having a receptacle, a flat plate welded to the bottom of the receptacle, with opposing edges of said plate bent downwardly and inwardly to form parallel straight guides and a pair of stationary contacts, combined with a removable unitary heater assembly comprising a rectangular slab having resistance elements embedded therein, said slab having opposite sides undercut to form edges adapted to engage slidably said guides on the plate, and a continuous unemcumbered flat upper surface, a pair of contacts near one end of the slab parallel with said guided edges adapted to engage the stationary contacts on the table, a control device at the other end of the slab, a thermostat intermediate said contacts and control device, and conductors interconnecting the contacts, thermostat and resistance elements, and supports affixed directly to the underside of the slab below the guide-engaging edges for the contacts, control device, thermostat and conductors.

2. A removable unitary heater assembly, comprising a rectangular slab having resistance elements embedded therein, said slab having opposite sides undercut to form edges by which it may be supported and a continuous unemcumbered fiat upper surface, an angle bracket having one of its flanges permanently afl'ixed to the underside of the slab near the rear end of the slab, a pair of contacts in the other flange of said angle bracket parallel with the supporting edges of the slab, an angle bracket near the front end of the slab having one of its flanges adjustably attached to the underside of the slab, a thermostat directly aiiixed to the underside of the slab intermediate said angle brackets, a control device for the thermostat extending through the angle bracket near the front end of the slab, and conductors under the slab interconnecting the contacts, the thermostat and the resistance elements.

3. A heating table having spaced parallel straight guides and a pair of stationary contacts, combined with a removable unitary heater assembly comprising a rectangular slab having resistance elements embedded therein, said slab having opposite sides undercut to form edges adapted to engage slidably said guides on the table, and a. continuous unemcumbered flat upper surface, an angle bracket having one of its flanges permanently affixed to the underside of the slab near the rear end of the slab, a pair of contacts in the other flange of said angle bracket parallel with the supporting edges of the slab, an angle bracket near the front end of the slab having one of its flanges adjustably attached to the underside of the slab, a thermostat directly afixed to the underside of the slab intermediate said angle bracket, a control device for the thermostat extending through the angle bracket near the front end of the slab, and conductors under the slab interconnectin the contacts, the thermostat and the resistance elements.

WOLFGANG STEPHAN;

REFERENCES CITED The following references are of record in the fil of this patent:

UNITED STATES PATENTS Number Name Date 2,107,173 Bauer Feb. 1, 1938 2,277,439 Jepson Mar. 24, 1942 2,288,510 Brannon June 30, 1942 2,306,979 Potsdam Dec. 29, 1942 2,424,412 Myers July 22, 1947 2,430,194 Snyder Nov. 4, 1947 2,448,617 Owens Sept. 7, 1948 FOREIGN PATENTS Number Country Date 80,951 Switzerland Apr. 16, 1919 

